Versions with magnesium may cause diarrhea, and brands with calcium or aluminum may cause constipation and rarely, longterm use may cause kidney stones. Long term use of versions with aluminum may increase the risk for getting osteoporosis.
^U.S. Department of Health and Human Services, National Institutes of Health, U.S. National Library of Medicine. Page last updated: 07 November 2014 Medline Plus: Taking Antacids
^Zajac, P; Holbrook, A; Super, ME; Vogt, M (March–April 2013). "An overview: Current clinical guidelines for the evaluation, diagnosis, treatment, and management of dyspepsia". Osteopathic Family Physician5 (2): 79–85. doi:10.1016/j.osfp.2012.10.005.
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